1. Field of the Invention
The present invention relates generally to a remotely readable meter register encoder and more particularly to electronic circuitry used in combination with the encoder to provide a self-contained, and universally adaptable meter register and encoder assembly for use in remote meter reading system applications.
2. Description of the Prior Art
The present invention finds particular application in the utility industry, where meters and their attendant encoders are automatically read over a communication line to collect utility consumption data for billing a consumer according to the amount of his electrical energy, water, and gas consumption.
There are various types of encoders frequently in use in automatic meter reading systems. These encoders range from parallel read-out devices to pulse indicator type devices, which provide switch closer output signals representative of consumer data. Another type of encoder is of the serial read-out type. It is this type in which the present invention finds an advantageous use. An encoder of this latter type, and various features thereof, is disclosed in U.S. Pat. Nos. 3,846,789 and 3,875,406. Also, the circuitry of the present invention, and an encoder utilizing that circuitry, is diclosed in U.S. Pat. application Ser. No. 48,537 filed on even date herewith entitled "Optical Encoder and Timing Generator System for Automatic Meter Reader", to Donald M. Ham and assigned to the assignee of the present invention. Further, a representative system of the type suitable for implementation of the present invention is disclosed in U.S. Pat. No. 4,135,181 entitled "Automatic Remote Meter Reading and Control System", also assigned to the assignee of the present invention. In this system, the encoder communicates with an external device called a meter terminal unit.
A completely self-contained remotely readable meter register and encoder assembly provides, inter alia, the advantages of, (1) lower cost, because it allows standardization and can be easily manufactured in large quantities, (2) readily adaptable to implementation (eg. plug-in capability) and (3) built in reliability by the use of well proven circuitry which does not have to be redesigned each time the encoder is used in a different application or environment. Also by incorporating all of the encoder power supply, readout and timing circuitry within the meter and encoder, additional economics and installation flexibility in the design can be achieved. With this design flexibility, sufficient signal drive can be achieved, which allows the encoder to be mounted either close to or far away from the external device (such as a meter unit) with which the encoder communicates. The ability to mount the encoder a considerable distance from the external device can be of significant value when installation constraints preclude the adjacent installation of the encoder and the external device.
In view of the preceding, it is therefore desirable to provide a completely self contained meter register encoder apparatus which contains its own power supply and signal read-out electronics and which is universally suitable for a variety of metering applications.